Methods and devices for protecting a passageway in a body when advancing devices through the passageway

ABSTRACT

A liner is advanced through a narrowed region in a vessel such as the internal carotid artery. The liner is advanced through the narrowed region in a collapsed position. A stent is then advanced through the liner and expanded to open the narrowed region. The liner may also have an anchor which expands an end of the liner before the stent is introduced.

BACKGROUND OF THE INVENTION

The present invention is directed to methods and devices for protectinga passageway in a body when advancing devices through the passageway. Aspecific application of the present invention is for treatment of bloodvessels although the invention may be used in any part of the body. Forexample, the present invention is used to protect blood vessels duringintravascular procedures for treating aneurysms, arteriovenousmalformations, and atherosclerotic disease of vessels. A particularapplication of the present invention is for atherosclerotic disease ofthe carotid arteries or saphenous vein grafts. Carotid arteryatherosclerotic occlusive disease contributes to hundreds of thousandsof strokes annually in the United States. Atherosclerotic disease of theinternal carotid artery is particularly problematic since plaque fromthe internal carotid artery leads directly to the cerebral vasculature.

A conventional method of treating carotid artery occlusive disease is bysurgical removal of the plaque (carotid endarterectomy). The carotidartery is opened surgically, the plaque is removed and the carotidartery is then closed. Carotid endarterectomies have demonstratedsignificant clinical benefit over conservative treatment with medicationby reducing strokes over the next five years. Although carotidendarteretomy reduces strokes over a period of time after the procedure,the procedure still has a 6% risk of death or stroke.

Another method of treating carotid artery disease is to useinterventional devices such as stents. A problem with treating carotidartery occlusive disease with stents is that the user is wary ofdislodging plaque when advancing the stent through the carotid artery.Any plaque which breaks free during introduction of the stent travelsdirectly to the patient's brain and can cause a stroke or death.

Yet another method of treating carotid artery occlusive disease is tointroduce a filter through the carotid artery to trap emboli releasedduring subsequent deployment of a stent or angioplasty balloon. Thismethod suffers the same drawback in that advancement of the filteritself may dislodge plaque. Moreover, exchange of various therapeuticcatheters over the filter element result in undesirable movement of thefilter with attendant risk of losing filtered emboli or damaging thevessel wall with the filter.

The present invention is directed to improved methods of protecting abody passageway when advancing devices through the body passageway. Thepresent invention is also directed to improved methods of treatingatherosclerotic vessels and, in particular, occlusive disease of theinternal carotid artery.

SUMMARY OF THE INVENTION

In accordance with the objects of the invention, a liner is provided toprotect a body passageway during introduction of other devices into thepassageway. In a specific application, the methods and devices of thepresent invention are used to protect blood vessels, such as theinternal carotid artery, during intravascular procedures. It isunderstood that use of the present invention for protection of bloodvessels is discussed as an example of how the present invention may beused, however, the invention may be used in any other part of the bodywithout departing from the scope of the invention. The liner iscollapsed for introduction into the patient and advanced to a narrowedregion of a blood vessel. The liner is passed through a region of theblood vessel in the collapsed condition and an intravascular device,such as a stent or filter, is then introduced into the liner. The linermay be used to protect vessels from any type of problem includingatherosclerotic disease, perforation, aneurysm or AVM.

The liner protects the vessel as the intravascular device is passedthrough the region to prevent the device from dislodging plaque. Whenthe device is a stent, the stent is preferably expanded within the linerto trap the liner between the stent and the vessel. The liner may beexpanded by the stent or may be partially or fully expanded beforeintroduction of the stent. The devices and methods of the presentinvention are particularly useful for treating occlusive disease of theinternal carotid artery. The liner may be any suitable material andsuitable materials include expanded PTFE, woven dacron, nylon, lowdurometer silicone, or thin-walled polyethylene.

The liner is preferably mounted to a delivery catheter and is advancedover a guidewire. The liner may have an anchor at a proximal end whichis used to open the proximal end of the liner. The anchor may beself-expanding or balloon expandable. Once the proximal end of the lineris opened, the liner can be designed so that blood pressure opens theliner. Alternatively, the liner may open automatically or may be openedwith a separate device, the delivery catheter or the stent itself. Whentreating occlusive disease of the internal carotid artery, the anchormay be positioned completely in the internal carotid artery or mayextend from the common carotid artery across the bifurcation of theinternal and external carotid arteries and into the internal commoncarotid. The anchor preferably has an open structure which permits bloodflow into the external carotid artery.

The liner may be an elastic liner or may be folded into a collapsedposition. The liner may be collapsed in any suitable manner andpreferably has a number of folded sections which are wrapped around oneanother. The folded sections are preferably adhered to one another tohold the liner in the collapsed position. The folded sections may beadhered together by application of heat or with an adhesive or coating.The distal end of the liner may be coated to form a curved surface whichcovers the ends of the folded sections. Alternatively, the ends of theliner may be scalloped or contoured so that when folded the edge tapersdown more cleanly.

The liner may also be designed to evert when expanding. The evertingliner reduces sliding between the liner and vessel so that plaque is notdislodged when introducing the liner. An end of the everting liner maybe releasably attached to the delivery catheter.

The proximal end of the liner may also be opened with an expandabledevice, such as a balloon, on the delivery catheter rather than with ananchor attached to the liner. Once the proximal end is open, the stentor other device is advanced through the liner.

In yet another aspect of the invention, the catheter holds the proximalend partially open. The stent or other device is then advanced throughthe open proximal end. The liner can be released when using a stent ormay be removed after use.

These and other features and advantages of the invention will becomeevident from the following description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a system for advancing devices through a narrowed region ofa blood vessel such as the internal carotid artery.

FIG. 2 shows a liner advanced through the narrowed region in a collapsedposition.

FIG. 3 shows the liner detached from the delivery catheter and expanded.

FIG. 4 shows only the proximal end of the liner expanded with an anchor.

FIG. 5 shows the liner having openings or perforations.

FIG. 6A shows the liner having a woven or braided configuration.

FIG. 6B shows the liner having a radiopaque maker and a scalloped distalend.

FIG. 7 shows the liner folded into six folded sections.

FIG. 8 shows the folded sections wrapped around one another.

FIG. 9 shows an end view of the liner of FIG. 7.

FIG. 10 shows an end view of the liner of FIG. 8 with the liner wrappedaround a guidewire.

FIG. 11 shows the liner having four folded sections.

FIG. 12 shows the liner of FIG. 11 with the folds wrapped around oneanother.

FIG. 13 shows a coating over a distal end of the liner.

FIG. 14 shows the coating extending over the length of the liner.

FIG. 15 is a cross-sectional view of the liner and coating with fourfolded sections.

FIG. 16 is a cross-sectional view of the liner and coating with sixfolded sections.

FIG. 17 shows a sheath covering the liner in the collapsed condition.

FIG. 18 shows a filament tearing a distal end of the sheath.

FIG. 19 shows the liner attached to the anchor.

FIG. 20 shows the liner attached to a tapered anchor.

FIG. 21 shows an anchor contained entirely within the internal carotidartery.

FIG. 22 shows the balloon expanding the anchor and blocking blood flowinto the internal carotid artery.

FIG. 23 shows the liner and anchor of FIG. 22 deployed.

FIG. 24 shows a balloon-expandable stent introduced into the liner.

FIG. 25 shows the stent expanded.

FIG. 26A shows an elongate element which opens the distal end of theliner.

FIG. 26B shows the elongate element contained within a tube duringdelivery of the liner.

FIG. 26C shows the elongate element of FIG. 26B advanced into a pocketof the liner to open the proximal end of the liner.

FIG. 26D shows the stent introduced into the liner of FIG. 26C.

FIG. 27 shows the delivery catheter for the anchor used to deliver astent into the liner.

FIG. 28 shows the distal end of the stent of FIG. 27 expanded to trapplaque behind the liner.

FIG. 29 shows the delivery catheter for the anchor used to deliver adistal anchor.

FIG. 30 show the delivery catheter in position for delivering the distalanchor.

FIG. 31 shows the distal anchor deployed so that the proximal and distalends of the liner are expanded.

FIG. 32 shows another stent delivered between the proximal and distalanchors.

FIG. 33 shows the stent of FIG. 32 expanded.

FIG. 34 shows a delivery catheter having an expandable section foropening the proximal end of the liner.

FIG. 35 shows the proximal end of the liner opened with the expandablesection.

FIG. 36 shows the stent advanced through the liner.

FIG. 37 shows the stent partially expanded.

FIG. 38 shows the stent expanded into contact with the vessel wall andthe liner released from the delivery catheter.

FIG. 39 shows the stent fully expanded.

FIG. 40 show a filter passed through the liner.

FIG. 41 shows the liner everting when deployed.

FIG. 42 shows the liner partially everted.

FIG. 43 shows the liner almost completely everted and the distal endreleased.

FIG. 44 shows the liner released from the delivery catheter.

FIG. 45 shows another delivery catheter which holds the proximal end ofthe liner open.

FIG. 46 shows the stent advanced through the liner of FIG. 45.

FIG. 47 shows another delivery catheter for the liner.

FIG. 48 shows still another delivery catheter for the liner.

FIG. 49 shows yet another delivery catheter for the liner.

FIG. 50 shows a distal end of the liner trapped in a fold.

FIG. 51 shows a kit having devices and instructions for use inaccordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A system 2 for protecting vessels during intravascular procedures isshown in FIGS. 1-4. Although the present invention is described inrelation to treatment of atherosclerotic disease of the internal carotidartery and the particular problems encountered when working in thecarotid arteries, the liner may be used in other vessels such assaphenous vein grafts of coronary bypass procedures, iliac and coronaryarteries. A guide catheter 4 is introduced through the femoral arteryand advanced to the common carotid artery in the conventional manner.The guide catheter 4 has a hemostasis valve 6 which receives a linerdelivery catheter 8. The guide catheter 4 may be omitted withoutdeparting from the scope of the invention.

A liner 10 is used to protect the body passageway when passing otherdevices through the body passageway. For example, the liner 10 may beused to protect the carotid artery to prevent plaque from beingdislodged when passing other devices through the carotid artery. Aproximal end 11 of the liner 10 may be attached to an anchor 12 whichexpands and opens the liner 10 and holds the liner 10 against the vesselwall to reduce or eliminate flow around the liner. The liner ispreferably nonmetallic and is relatively flexible to conform to the bodypassageway. The anchor 12, as will be discussed below, is mounted to oneend of the liner 10 while the other end of the liner 10 is preferablyfree.

The liner 10 is advanced through the vessel in the collapsed conditionof FIG. 2 so that the liner 10 can be advanced through small or highlystenosed vessels. After the liner 10 is in position, other devices, suchas a stent 26 (FIG. 25) or filter (FIG. 40), may be passed through theliner 10 so that the liner 10 prevents contact between the device andthe vessel wall. The liner 10 may also be used to protect the vesselwhen advancing other devices such as angioplasty balloons, drug deliverycatheters, laser catheters or ultrasound catheters. FIG. 3 shows bothends of the liner 10 opened to trap plaque behind the liner 10 so thatloose plaque cannot flow downstream. The liner 10 is preferablydelivered over a conventional guidewire 15 which has a 0.010-0.018 inchdiameter but may be of any other suitable size depending upon thevascular site.

The liner 10 is preferably made of expanded PTFE having a thickness of0.006 to 0.002 inch, more preferably 0.001 to 0.002 inch and mostpreferably about 0.001 +/−0.0005 inch although any other suitablematerial may be used. For example, the liner 10 may have a wovenconstruction such as silk or polyester as shown in FIG. 5. The liner 10may also have small openings 25 or perforations which act similar to afilter in that they permit blood to flow through but prevent largeemboli from escaping (FIG. 6A). The openings 25 also may promote tissuegrowth. Referring to FIG. 6B, the liner 10 may also have a scallopeddistal end 7 to form a smoother transition at the distal end whencollapsed. The liner 10 may also have a radiopaque marker 9, such as a0.002 inch by 0.008 inch platinum ribbon, embedded, sewn, or folded intothe liner 10. The liner 10 may have the markers 9 extendinglongitudinally (FIG. 6B) or circumferentially. When the markers 9 extendlongitudinally, three markers 9 are preferably provided 120 degreesapart.

The liner 10 may also be elastic so that the liner 10 remainssubstantially cylindrical and without folds in the collapsed andexpanded positions. When using an elastic liner 10, the liner 10 ispreferably a tube of low durometer silicone, latex or natural rubber,thermoplastic elastomers such as Kraton or hydrogenated thermoplasticisoprenes having a thickness of 0.001 to 0.0005 inch. Alternatively, theliner 10 could be made of an inelastic but plastically deformablematerial. Initially the liner 10 would be sized to allow easy passage ofthe devices such as the balloons, stents and filters described herein.The liner 10 is then plastically deformed by the devices which passtherethrough. For example, a pre-dilatation balloon may be introduced todilate the liner 10. The stent 27 can then be advanced into the dilatedliner 10 and expanded to open the narrowed vessel. Expansion of thestent continues plastic deformation of the liner 10 to a final size. Anyof the liners 10 described herein may be substituted for any of theother liners 10 without departing from the scope of the invention.

FIGS. 7-12 show a preferred method of collapsing the liner 10. The liner10 is folded longitudinally along creases 13 to create at least 2 andpreferably 4-6 folded sections 14. Four folded sections 14 are shown inFIG. 11 and six folded sections 14 are shown in FIGS. 7 and 9. The folds14 are then wrapped as shown in FIGS. 8, 10 and 12. The liner 10 may, ofcourse, be wrapped in any other manner. For example, the liner 10 may bespiral wrapped or randomly compressed and set with high pressure and/orheat. The folded sections 14 may be adhered to one another byapplication of heat which holds the folded sections 14 together withoutmelting and fusing the sections 14 together. Another method of holdingthe liner 10 in the collapsed position is to apply an adhesive 16 suchas medical grade glue, cyanoacrylates, epoxies, ultraviolet activatedadhesives, low molecular weight polyvinyl alcohol polymer, gelatin andsucrose. The liner 10 may also be partially or completely covered with acoating 20 which dissolves in blood such as sugar (FIGS. 13-16). Inparticular, the distal end 19 of the liner 10 may be covered with thecoating 20 to form a smooth, atraumatic end as shown in FIG. 13. Thecoating 20 may extend along the length of the liner 10 as shown in FIG.14 or may be only at the distal end or intermittent as shown in FIG. 13.

The liner 10 may also be covered by a removable sheath 21 as shown inFIGS. 17 and 18. The sheath may be removed in any manner such as tearingalong perforations or with a chemical, thermal or electrolyticallyseverable bond. A filament 23 may also be used to tear the sheath 21 asshown in FIGS. 17 and 18. The filament 23 may have both ends extendingthrough the catheter rather than having one end extend out of thecatheter. The filament 23 is shown separated from the sheath 21 forclarity but would either pass inside the sheath 21 or would be partiallyembedded in the sheath 21. The sheath 21 can also be a simpleretractable sheath 21 as is known in the art.

Referring again to FIGS. 10 and 12, the liner 10 is collapsed onto theguidewire so that the liner 10 has an outer diameter at of no more than0.065 inch, more preferably no more than 0.040 inch, and most preferablyno more than 0.026 inch. Stated another way, the thickness β of theliner 10 is preferably no more than 0.015 inch, more preferably no morethan 0.012 inch, and most preferably no more than 0.008 inch whenmeasured in a radial direction. For a guidewire 15 having a 0.014 inchdiameter, the liner 10 is preferably collapsed so that the outerdiameter α is 0.020 to 0.032 inch, preferably about 0.026 inch, and thethickness β of the liner 10 is 0.004 to 0.008 inch, preferably about0.006 inch. For a guidewire 15 having a 0.018 inch diameter, the liner10 is preferably collapsed so that the outer diameter α is still about0.020 to 0.032 inch, preferably about 0.026 inch, and the thickness β ofthe liner 10 is 0.003 to 0.006 inch, preferably about 0.004 inch. Theliner 10 also has a high ratio of collapsed cross-sectional area toexpanded circumference in the range of 1:10 to 1:30 and preferably atleast 1:20.

The relatively small size of the liner 10 advantageously permits theliner 10 to be introduced through small and heavily stenosed vessels.The carotid artery is often occluded 95 to 98% and may have diameters assmall as 0.020 inch or even 0.010 inch before surgical or interventionalprocedures are performed. Conventional stents used in the internalcarotid artery have a collapsed diameter of about 0.065 to 0.092 inchand, thus, must often displace the plaque to pass through the vessel. Itis believed that some strokes which occur when using stents in thecarotid artery are caused by plaque which is dislodged when the stent isadvanced through and expanded within highly stenosed regions. The liner10 of the present invention protects the vessel as the stent or otherdevice is passed through the vessel. The liner 10 preferably has alength γ of at least 2 cm and preferably 2-10 cm (FIG. 2). The liner 10and anchor 12 have a diameter of 4-10 mm in the expanded condition withthe specific size selected depending upon the size of the vessel beingtreated. The relative dimensions shown in the drawing have beenexaggerated to illustrate the features of the invention. In fact, theliner 10 has a length to width ratio (γ to α)in the collapsed positionof at least 20 to 1, 50 to 1, 80 to 1, and even up to 200 to 1 dependingupon the particular application. The liner 10 preferably increases inouter diameter at least 5, more preferably at least 6 and mostpreferably at least 8 times when moving from the collapsed to expandedpositions.

Referring again to FIGS. 3 and 4, the anchor 12 may be attached to theproximal end 11 of the liner 10 to expand the end 11 of the liner 10,hold the liner 10 in position and reduce flow around the liner 10. Theanchor 12 may be any suitable device including a commercially availablenitinol or stainless steel stent such as the MULTILINK manufactured byACS and the NIR manufactured by Scimed. The liner 10 is attached to aportion of the anchor 12 with an adhesive, mechanical interconnection,thermal bond, suture or the like, or fused or soldered with radiopaquewire or ribbon. The liner 10 may, of course, be attached in any othermanner. The liner 10 may also be encapsulated between layers of expandedPTFE.

The anchor 12 and liner 10 may form a continuous, cylindrical shape inthe expanded position (FIG. 19) or the anchor 12 may have a taperedshape (FIG. 20). The tapered shape of the anchor 12 may be useful whenused in the carotid arteries with the small end positioned in theinternal carotid artery and the large end in the common carotid. Amethod of forming the expanded shape of FIG. 20 is for the anchor 12 tohave a larger diameter than the liner 10 so that the liner 10 holds anend of the anchor 12 at a smaller diameter. For example, the anchor 12may be a stent having an 8 mm diameter with the liner 10 having a 6 mmexpanded diameter so that the liner 10 holds the end 11 of the anchor 12to about 6 mm. Alternatively, the anchor 12 could be designed to expandto different predetermined diameters at different points along itslength by varying strut lengths along its length.

The anchor 12 is positioned within an anchor retention catheter 22 (FIG.2). The anchor 12 is naturally biased to the expanded condition of FIG.3 and is held in the collapsed position by the retention catheter 22.The anchor 12 is deployed by retracting the catheter 22 while an innerelement 24 holds the anchor 12 at the desired location in the vessel.The liner 10 is advanced over the guidewire 15 which is advanced aheadof the catheter 22.

The anchor 12 may be deployed to extend into the common carotid arteryat the bifurcation of the external and internal carotid arteries (FIG.2) or may be contained entirely within the internal carotid artery(FIGS. 21-23). The anchor 12 may also be deployed by inflating a balloon27 as shown in FIG. 21 or may be a shape memory material which is heatactivated. When using a balloon 27 to expand the anchor 12, the anchor12 is preferably a conventional nitinol or stainless steel stentalthough any suitable stent or device may be used. The balloon 27 ispreferably compliant so that a proximal portion of the balloon 27expands to occlude the vessel as shown in FIG. 21 before expansion ofthe anchor 12. Alternatively, the balloon could be non-compliant butdesigned to inflate at a lower pressure than that required to expand thestent. By occluding the vessel, blood flow through the vessel is stoppedso that even if plaque is released the plaque will not flow downstream.Further inflation of the balloon 27 (using inflation source 39) expandsthe anchor 12 into engagement with the vessel wall (FIG. 22). Any of theembodiments of the liner 10 described herein may be used with balloon orself-expanding anchors 12 and stents 26.

After the anchor 12 has been expanded, the liner 10 can be configured toautomatically open with blood pressure (FIG. 3). Alternatively, thecatheter 22 may be advanced through the liner 10 to partially open theliner 10. The device, such as the stent 26, may also be advanced throughthe liner 10 to open the liner 10. The liner 10 protects the vessel toprevent intravascular devices from dislodging plaque when passingthrough the vessel. The distal end of the liner 10 may also be openedwith an elongate element 29, such as a nitinol wire, advanced into theliner 10 to open the liner 10 as shown in FIG. 26A. The element 29 maybe advanced and retracted independently with an inner actuator 31.

Referring to FIGS. 26B and 26C, the elongate element 29A may also beadvanced into a pocket 35 in liner 10A. The pocket 35 is preferablyformed by simply inverting or everting the end of the liner 10A andattaching the end to another part of the liner 10A to form the pocket35. The elongate element 29A passes through a tube 41, preferably ahypotube, polymer tube or composite tube, which is releasably attachedto the pocket 35. The tube 41 is preferably released by heat,electrolytic detachment, mechanical detachment, dissolution of a bond byblood, or retraction of a retention cord although any suitable methodmay be used.

The elongate element 29A is preferably made of a superelastic material,such as nitinol, which forms a loop 47 in the expanded position. Theelongate element 29A is contained within the tube 41 when the liner 10Ais advanced through the vasculature. The liner 10A is advanced over theguidewire 15 by pushing the tube 41. When the user is ready to expandthe proximal end of the liner 10A, the element 29A is advanced into thepocket 35 so that the loop 47 opens the liner 10A as shown in FIGS. 26Cand 26D. After opening the proximal end of the liner 10A, the liner 10may be used in any manner described herein. For example, the stent 26may be advanced into the liner 10A to open the narrowed region of theblood vessel as described in further detail below and shown in FIGS. 26Dand 26E.

When the device introduced into the liner 10 is the stent 26, the stent26 is preferably expanded to open the narrowed portion of the vessel asshown in FIG. 25. The stent 26 is mounted to a balloon 33 which iscoupled to an inflation source 37 (FIG. 1) for inflating the balloon 33.The stent 26 is preferably a conventional nitinol or stainless steelstent. The delivery catheter 22 is preferably introduced into the liner10 as shown in FIG. 27 with the distal end of the catheter 22 positionedbeyond the end of the liner 10. The catheter 22 is then retracted toexpose the distal end of the stent 26. The distal end of the stent 26 ispreferably opened first so that plaque is trapped between the anchor 12and stent 26 when expanding the rest of the stent 26. The liner 10 mayhave the openings 25 (FIG. 5) which effectively filter blood trappedbehind the liner 10 and help to equalize pressure on opposite sides ofthe liner as the stent 26 is expanded. The catheter 22 may also be usedto deliver a distal anchor 43 which holds the distal end of the liner 10open as shown in FIGS. 29-31. Another stent 45 can then be delivered toexpand the liner 10 between the anchor and distal anchor 43 (FIGS. 32and 33).

Referring to FIGS. 34-39, the proximal end of the liner 10 may beexpanded by delivery catheter 50 and then released so that the anchor 12is not required. The catheter 50 has an expanding section 32 which ispreferably inflatable but may also be mechanically actuated. Theexpanding section 32 is coupled to a lumen for inflating the expandingsection 32. The liner 10 is attached to the expanding section 32 withany suitable connection such as glue, suture, or soldered withradiopaque wire or ribbon. The liner 10 is preferably attached to theexpanding section 32 with a thread 34 which passes through the liner 10and expanding section 32. An end of the thread 34 is pulled to releasethe liner 10.

The expanding section 32 is inflated to expand the proximal end of theliner 10 as shown in FIG. 35. The stent 26 or other device may then bepassed through the liner 10 to open the liner 10 further as shown inFIG. 35. Referring to FIG. 38, the stent 26 is partially expanded sothat the liner 10 is held firmly in place by the stent. The liner 10 isthen detached by pulling the thread 34 and the stent 26 is fullyexpanded. Referring to FIG. 40, the device may also be a filter 36 whichis advanced through the liner 10 to trap dislodged plaque during anangioplasty, stent or other procedure. The liner 10 may then be removedbefore removing the filter 36 or may be used to line the vessel whendeploying the stent 26.

Referring to FIGS. 41-44, the liner 10 may also be everted when movingfrom the collapsed to expanded positions. The liner 10 has the anchor 12which is self-expanding and held in the collapsed position by retentioncatheter 37. Pusher element 38 holds the anchor 12 in place whileretracting the retention catheter 37. A proximal end 40 of the liner 10is releasably attached to an inner member 42. The liner 10 ispressurized, preferably with saline, using lumen 44 in the pusherelement 38. Once the liner 10 is pressurized, the inner member 42 isadvanced so that the liner 10 everts and moves through the vessel asshown in FIGS. 42-43. An advantage of the everting liner 10 is thatsliding forces between the liner 10 and the vessel wall are reduced whenadvancing the liner 10.

After the liner 10 has been fully everted, the retention catheter 37 isretracted so that the anchor 12 expands and holds the proximal end ofthe liner 10 open. The liner 10 is then detached from the inner member42. The liner 10 may have a mechanical connection which is released witha push rod or guidewire 43. The liner 10 may also have a severable bondwith the inner member 42 such as a thermally, chemically orelectrolytically severable bond using the guidewire 43. The device, suchas the stent 26, is then delivered through the liner 10.

Referring now to FIGS. 45 and 46, the liner 10 may also be held openslightly at the proximal end 11 by delivery catheter 60. The proximalend 11 of the liner is preferably held open to a diameter of 6 mm to 8mm or 4 Fr to 7 Fr. One or more filaments 62 hold the liner to thecatheter 60. The liner 10 extends over the distal end of the catheter 60but may also be mounted inside the catheter 60. The filaments are shownseparated from the body of the catheter 60 for clarity but would, ofcourse, either pass through the catheter or be held close to thecatheter 60. The distal end of the stent 26 is inflated first to trapthe plaque behind the liner 10 and reduce flow around the liner 10. Therest of the stent 26 is then expanded in the conventional manner.

Referring to FIG. 47, another catheter 70 for delivering the liner 10 isshown wherein the same or similar reference numbers refer to the same orsimilar structure. The catheter 70 operates similar to catheter 22described above in that the liner 10 is mounted to the self-expandinganchor 12. The anchor 12 is held in the collapsed position of FIG. 47 byan outer wall 72 of the catheter 70. The outer wall 72 is retracted toexpose the anchor 12 and permit the anchor 12 to expand.

The liner 10 is positioned between a flexible sheath 74 and an innertube 76. The sheath 74 and inner tube 76 prevent the liner 10 fromcontacting the walls of the vessel and guidewire 15 when the liner 10 isadvanced through the vasculature. The sheath 74 and tube 76 also holdthe liner 10 in the collapsed position although the liner 10 may becollapsed without requiring the sheath 74 and tube 76. The sheath 74 isattached to the outer wall 72 and is retracted together with the outerwall 72.

A shaft 80 extends through the catheter 62 and a flexible shaftextension 82 extends from the shaft 80. The shaft extension 82 and innertube 76 provide a relatively flexible distal portion to navigatetortuous vessels such as the cerebral vasculature. The flexible shaftextension 82 may be a coil 84 as shown in FIG. 47 or may be a tube 86 ofmaterial as shown in FIG. 48. A distal portion 88 of the catheter 70,which extends from the distal end of the shaft 80, is preferably moreflexible than a proximal portion 90 which terminates at the end of theshaft 80.

Referring to FIG. 47, the guidewire 15 passes through slots 93, 95 inthe outer wall 72 and shaft 80 for loading the device on the guidewire15. Referring to FIG. 48, the guidewire 15 may also pass through slots92, 97, 99 in the outer wall 72, inner tube 76 and shaft extension 82.The catheter 70 may, of course, have a continuous lumen which extends tothe proximal end of the catheter 70. Referring again to FIG. 47, ahandle 94 is attached to the outer wall 72 and is pulled relative to theshaft 80 to retract the sheath 74 and outer wall 72. The outer wall 72is preferably made of high density polyethylene having a thickness ofabout 0.005 inch and an outer diameter of 0.040 to 0.070 inch,preferably about 0.055 inch. The outer wall 72 preferably has a lengthof 110 to 150 cm and preferably about 135 cm. The sheath 74 ispreferably made of linear low density polyethylene having a wallthickness of about 0.002 inch and an outer diameter of about 0.049 inch.The inner tube 76 is preferably made of polyimide having a wallthickness of 0.0005 to 0.001 inch and an outer diameter of 0.014 to0.026 inch, more preferably 0.018 to 0.024 inch and most preferablyabout 0.022 inch. The liner 10 is collapsed to have a diameter, length,thickness and length to thickness ratios as described above when mountedto the tube 76. The shaft 80 is preferably a 0.022 inch diameterstainless steel mandrel and the shaft extension 82 is preferably astainless steel coil. The shaft extension is fused to the inner tube 76(FIG. 47). The extension 82 may also be a tube of linear low densitypolyethylene which is extruded and then irradiated with 25/30 Mrads toan outer diameter of about 0.040 and a wall thickness of about 0.018inch (FIG. 48). Any other suitable materials may be used withoutdeparting from the scope of the invention.

The catheter 70 and liner 10 are used in substantially the same manneras the catheters and liners 10 described above and the discussion aboveis equally applicable here. The liner 10 is advanced over the guidewire15 to a narrowed region of a blood vessel such as the internal carotidartery. The liner 10 and catheter have a small profile, as discussedabove and incorporated here, so that the liner 10 may be advanced intothe narrowed region without dislodging plaque. When the liner 10 is atthe desired location, the handle 94 and shaft 80 are manipulated toretract the sheath 74 and the outer wall 72. When the outer wall 72 andsheath 74 are retracted, the anchor 12 is free to expand. The liner 10may then be used in the manner described above. For example, the stent26 or filter 36 may be advanced into the liner 10.

Referring to FIG. 49, another catheter 100 for delivering the liner 10is shown. The catheter 100 has the self-expanding anchor 12 which isheld in the collapsed position by a collar 102. An arm 104 is attachedto the collar 102 which in turn is attached to a first core-wire 106.The first core wire 106 passes through a shaft 108 which has a handle110 mounted to the proximal end. The handle 110 is retracted to pull thecore wire 106, first arm 104 and collar 102 for releasing theself-expanding anchor 12.

A tube 112 is fused to the shaft 108 and an inner tube 114 is attachedto the tube 114. The arm 104 travels in a slot 116 in the tube 114 tostabilize retraction of the collar 102. The tube 112 and inner tube 114form a lumen 118 through which the guidewire 15 passes.

Referring to FIG. 50, the distal end of the liner 10 is locked into afold 120 at the end of the inner tube 114. A wire loop 122 holds theliner 10 in the fold 120. The wire loop 122 is preferably attached tothe collar 102 with a wire 124 embedded in the collar 102. The wire loop122 is retracted together with the collar 102 so that the distal end ofthe liner 10 is released as the collar 102 is retracted. The wire loop122 is preferably a 0.005 inch diameter stainless steel wire. The fold120 is preferably made of silicone although other suitable materials maybe used. The shaft 108 is preferably made of stainless steel hypotubehaving a wall thickness of about 0.005 inch and an outer diameter ofabout 0.024 inch. The tube 112 is preferably made of inear low densitypolyethylene having a wall thickness of about 0.004 inch and an outerdiameter of about 0.040 inch. The inner tube 114 is preferably made ofpolyimide having a thickness of 0.0005 inch and an outer diameter ofabout 0.022 inch. The liner 10 is deployed and used in substantially thesame manner as described above and the discussion above is applicablehere.

The present invention is also directed to kits 124 which include variousassemblies as described above. For example, the kit 124 may include theliner 10, delivery catheter 22 and instructions for use 126 settingforth any of the methods described herein as shown in FIG. 51. The kitsmay, of course, also include the stent(s) 26, anchors 12 and stentdelivery catheter(s) 22 and/or the filter 36 as well. The kits 124 willusually include a container 126, such as a pouch, tray, box, tube, orthe like, which contains the devices as well as the instructions for use128. The instructions for use 128 may be set forth on a separateinstructional sheet within the package or printed in whole or in part onthe packaging itself. Optionally, other system components useful forperforming the methods of the present invention could be provided withinthe kit 124, including guidewires, introductory sheaths, guidingcatheters, and the like. Any of the devices described herein may form akit with instructions setting forth a method of the present invention.

While the above is a complete description of the preferred embodimentsof the invention, various alternatives, modifications, and equivalentsmay be used. Therefore, the above description should not be taken aslimiting the scope of the invention which is defined by the appendedclaims. For example, any of the delivery catheters may have a balloonfor occluding the vessel while delivering the liner or advancing thedevice through the liner and any of the liners may have perforations tofilter blood or may be made of a tightly woven material. Furthermore,the preferred dimensions described herein with respect to any of theembodiments is equally applicable to other embodiments.

What is claimed is:
 1. A method of opening a narrowed region in a bloodvessel, comprising the steps of: providing a liner movable from acollapsed condition to an expanded condition; advancing the liner to anarrowed region of a blood vessel with the liner in the collapsedposition; passing at least a portion of the liner into the narrowedregion of the blood vessel in the collapsed position; positioning astent in the liner after the liner has been positioned in the narrowedregion of the blood vessel so that the stent is also positioned in thenarrowed region of the blood vessel, the liner preventing the stent fromcontacting the narrowed region of the blood vessel; and expanding thestent so that the stent expands the liner and the narrowed region of theblood vessel simultaneously.
 2. The method of claim 1, wherein: theadvancing and passing steps are carried out with the blood vessel beinga vessel selected from the group consisting of the internal carotidartery and saphenous vein graft.
 3. The method of claim 1, furthercomprising the step of: expanding at least one end of the liner beforeexpanding the stent in the narrowed region.
 4. The method of claim 1,wherein: the entire liner is expanded by the stent.
 5. The method ofclaim 1, wherein: the providing step is carried out with the liner beingmounted to a delivery catheter.
 6. The method of claim 1, wherein: theproviding step is carried out with the liner having an expandable anchorcoupled to the liner.
 7. The method of claim 6, wherein: the providingstep is carried out with the anchor attached to the proximal end of theliner.
 8. The method of claim 6, further comprising the steps of:holding the anchor in a collapsed position; and the expanding step iscarried out by releasing the anchor so that the anchor moves intocontact with the vessel wall and toward an expanded condition.
 9. Themethod of claim 8, wherein: the anchor is expanded in the internalcarotid artery or saphenous vein graft.
 10. The method of claim 9,wherein: the anchor expanding step is carried out so that the anchor ispositioned at the bifurcation of the internal and external carotidarteries.
 11. The method of claim 1, wherein: the providing step iscarried out with the liner being carried by a delivery catheter, theliner extending from a distal end of the delivery catheter.
 12. Themethod of claim 1, wherein: the advancing the step is carried out byadvancing the liner over a guidewire.
 13. The method of claim 12,wherein: the providing step is carried out with the liner having aradial thickness of less than 0.020 inch in the collapsed position, thethickness being measured in a radial direction relative to a hole inwhich a guidewire is positioned.
 14. A method of protecting a bodypassage, comprising the steps of: providing a liner movable from acollapsed condition to an expanded condition, the liner everting whenmoving from the collapsed condition to the expanded condition; advancingthe liner to a region of a passageway in a body with the liner in thecollapsed position; passing at least a portion of the liner into theregion of the passageway in the collapsed position, at least a portionof the liner everting when moving from the collapsed position to theexpanded position; positioning a device in the liner so that the deviceis also positioned in the region of the passageway, the liner preventingthe device from contacting the region of the passageway.
 15. A method ofopening a narrowed region in a blood vessel, comprising the steps of:providing a liner movable from a collapsed condition to an expandedcondition, the liner having an expandable anchor coupled to the liner;advancing the liner to a narrowed region of a blood vessel with theliner in the collapsed position; passing at least a portion of the linerinto the narrowed region of the blood vessel in the collapsed position;expanding the anchor with a balloon; positioning a stent in the linerafter the liner has been positioned in the narrowed portion so that thestent is also positioned in the narrowed region of the blood vessel, theliner preventing the stent from contacting the narrowed region of theblood vessel; and expanding the stent so that the stent expands theliner and the narrowed region of the blood vessel simultaneously.
 16. Amethod of opening a narrowed region in a blood vessel, comprising thesteps of: providing a liner movable from a collapsed condition to anexpanded condition, the liner being at least partially covered by acoating in the collapsed position, the coating dissolving in blood;advancing the liner to a narrowed region of a blood vessel with theliner in the collapsed position; passing at least a portion of the linerinto the narrowed region of the blood vessel in the collapsed position;positioning a stent in the liner after the liner has been positioned inthe narrowed portion so that the stent is also positioned in thenarrowed region of the blood vessel, the liner preventing the stent fromcontacting the narrowed region of the blood vessel; and expanding thestent so that the stent expands the liner and the narrowed region of thevessel simultaneously.
 17. A method of opening a narrowed region in ablood vessel, comprising the steps of: providing a liner movable from acollapsed condition to an expanded condition, the liner having a numberof folded sections in the collapsed condition, the distal end of theliner being covered with a coating which forms a curved, atraumaticsurface and covers a distal end of the folded sections; advancing theliner to a narrowed region of a blood vessel with the liner in thecollapsed position; passing at least a portion of the liner into thenarrowed region of the blood vessel in the collapsed position;positioning a stent in the liner after the liner has been positioned inthe narrowed portion so that the stent is also positioned in thenarrowed region of the blood vessel, the liner preventing the stent fromcontacting the narrowed region of the blood vessel; and expanding thestent so that the stent expands the liner and the narrowed region of theblood vessel simultaneously.
 18. The method of claim 15, wherein: theadvancing and passing steps are carried out with the blood vessel beinga vessel selected from the group consisting of internal carotid arteryand saphenous vein graft.
 19. The method of claim 15, further comprisingthe step of: expanding at least one end of the liner before expandingthe stent in the narrowed region.
 20. The method of claim 15, wherein:the entire liner is expanded by the stent.
 21. The method of claim 15,wherein: the providing step is carried out with the liner being mountedto a delivery catheter.
 22. The method of claim 15, wherein: theproviding step is carried out with the anchor attached to the proximalend of the liner.
 23. The method of claim 15, further comprising thesteps of: holding the anchor in a collapsed position; and the expandingstep is carried out by releasing the anchor so that the anchor movesinto contact with the vessel wall and toward an expanded condition. 24.The method of claim 15, wherein: the anchor is expanded in the internalcarotid artery or saphenous vein graft.
 25. The method of claim 16,wherein: the anchor expanding step is carried out so that the anchor ispositioned at the bifurcation of the internal and external carotidarteries.
 26. The method of claim 15, 16 or 17 wherein: the providingstep is carried out with the liner having a number of folded sections inthe collapsed position.
 27. The method of claim 26, wherein: the foldsare separated by longitudinal creases.
 28. The method of claim 26,wherein: the providing step is carried out with the folded sectionsbeing wrapped.
 29. The method of claim 26, wherein: the providing stepis carried out with at least two folded section.
 30. The method of claim15, wherein: the providing step is carried out with the liner beingcarried by a delivery catheter, the liner extending from a distal end ofthe delivery catheter.
 31. The method of claim 15, wherein: theadvancing the step is carried out by advancing the liner over aguidewire.
 32. The method of claim 31, wherein: the providing step iscarried out with the liner having a radial thickness of less than 0.020inch in the collapsed position, the thickness being measured in a radialdirection relative to a hole in which a guidewire is positioned.
 33. Amethod of opening a narrowed region in a blood vessel, comprising thestep of: providing a liner movable from a collapsed condition to anexpanded condition, the liner having a number of folded sections in thecollapsed position; advancing the liner to a narrowed region of a bloodvessel with the liner in the collapsed position; passing at least aportion of the liner into the narrowed region of the blood vessel in thecollapsed position; positioning a stent in the liner after the liner hasbeen positioned in the narrowed portion so that the stent is alsopositioned in the narrowed region of the blood vessel, the linerpreventing the stent from contacting the narrowed region of the bloodvessel; and expanding the stent so that the stent expands the liner andthe narrowed region of the blood vessel simultaneously.
 34. The methodof claim 33, 16 or 17, wherein: the advancing and passing steps arecarried out with the blood vessel being a vessel selected from the groupcomprising the internal carotid artery and saphenous vein graft.
 35. Themethod of claim 33, 16 or 17, further comprising the step of: expandingat least one end of the liner before expanding the stent in the narrowedregion.
 36. The method of claim 33, 16 or 17, wherein: the entire lineris expanded by the stent.
 37. The method of claim 33, 16 or 17, wherein:the providing step is carried out with the liner being mounted to adelivery catheter.
 38. The method of claim 33, 16 or 17, wherein: theproviding step is carried out with the liner having an expandable anchorcoupled to the liner.
 39. The method of claim 38, wherein: the providingstep is carried out with the anchor attached to the proximal end of theliner.
 40. The method of claim 38, further comprising the step of:expanding the anchor with a balloon.
 41. The method of claim 38, furthercomprising the steps of: holding the anchor in a collapsed position; andthe expanding step is carried out by releasing the anchor so that theanchor moves into contact with the vessel wall and toward an expandedcondition.
 42. The method of claim 38, wherein: the anchor is expandedin the internal carotid artery or saphenous vein graft.
 43. The methodof claim 42, wherein: the anchor expanding step is carried out so thatthe anchor is positioned at the bifurcation of the internal and externalcarotid arteries.
 44. The method of claim 33, 16 or 17, wherein: thefolds are separated by longitudinal creases.
 45. The method of claim 33,16 or 17, wherein: the providing step is carried out with the foldedsections being wrapped.
 46. The method of claim 33, 16 or 17, wherein:the providing step is carried out with at least two folded sections. 47.The method of claim 33, 16 or 17, wherein: the providing step is carriedout with the folded sections being adhered to one another to hold thefolded sections in the collapsed position.
 48. The method of claim 33,16 or 17, wherein: the providing step is carried out with the foldedsections adhering to one another by application of heat to the foldedsections.
 49. The method of claim 33, 16 or 17, wherein: the providingstep is carried out with the folded sections adhering to one anotherwith an adhesive.
 50. The method of claim 33, 16 or 17, wherein: theproviding step is carried out with the folded sections being adhered toone another with gelatin, sucrose, glue, low molecular weight polyvinylalcohol, suture, or fusion or soldered with radiopaque wire or ribbon.51. The method of claim 33, 16 or 17, wherein: the providing step iscarried out with the liner being carried by a delivery catheter, theliner extending from a distal end of the delivery catheter.
 52. Themethod of claim 33, 16 or 17, wherein: the advancing the step is carriedout by advancing the liner over a guidewire.
 53. The method of claim 52,wherein: the providing step is carried out with the liner having aradial thickness of less than 0.020 inch in the collapsed position, thethickness being measured in a radial direction relative to a hole inwhich a guidewire is positioned.